Therapeutic lamp



Aug. 21, 1928;

I 7 Filed July 26, 1926 *CROSS REFERENCE-'- 1,681,736 A. .A. KULL THERAPEUTIC LAMP 2 Sheets-Sheet 1 Snvenior Andrew/4. hall- EXAMINEE' REFERENCE Aug. 21, 1928.

' A. A. KULL 'THERAFEUTIC LAMP Filed July 26,1926

2 Sheets-Shed 2 amrcnior Andrey 14 fizz/Z I Patented Aug. 21, 1928.

UNITED STATES PATENT orl-"lcspi ANDREW KULL, OF MILTON, WISCONSIN, ASS IGNOB TO THE BURDICK CORPOB A- TION, OF MILTON, WI SCONSIN, A CORPORATION OF DELAWARE.

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Application filed July as, 1926. Serial No. 124,888. I 5/ a My invention relates to therapeutic lamps. It relates more particularly to an improved light and heat generatin unit or cartridge for use in thera eutic amps wherein the production of re and infra-red rays is of primaryconcern, although, of course, it may be applid to other lamps.

As heretofore constructed the radiant energy generating unit comprises a porcelain base, a post fixed in the base and carrying a head at its outer extremity. The resistor rods were held between this head and resilient supporting clips secured to the base. In use the head and also the clips sometimes became heated to a very high temperature, causing oxidation of the head and clip contacts and causing the spring supports to lose their resiliency; Since the parts were mounted on a porcelain base, there was little opportunity for the escape of heat from the unit. This condition was especiall' ag avated in the larger size units and a so w ere more than two resistor rods. were grouped together. The head, particularly, had a tendency to become overheated due to the fact that the most desirable arrangement of the rods was such that they were in close proximity'to each other near the head. In .addition, the head was in a position where it was subject to heating by the more or less concentration of rays from the reflector.

An object of myinvention is to provide an improved radiant energy generatin unit for use in therapeutic lamps, the unit eing constructed in an improved manner to prevent undue heating of the support for the resistors by which the radiant energy is developed upon the passage of an electric current. 1

Other objects will appear from the following description, reference being had to the accompanying drawings in which, Fig. 1 is a side elevation of the radiant en ergy generatin unit of my invention mounted in a. suitafile reflector which is shown partly in section; I a Fig. 2 is an end elevation of the radiant energy generating unit; Fig. 3 is a horizontal sectional view on the line-33 of Fig. 2;

Fig. 4 isa view similar to Fig. 1,'showing a modified construction of the radiant energy generating unit; a

Fig. 5 1s a fragmentaryplan view of the modified form of radiant energy generating unit,' and Fig. 6 is a sectional view thereof on the line 6-6 of Fig. 5.

The lamp comprises generally a parabolic reflector 6 carried on a plug receptacle housing 7, an electric screw plu receptacle 8 in the housing at the rear or c osed end, a handle 9 attached to the receptacle housing, and a radiant energy generating unit or cartridge 10 carried by the screw plug receptacle.

The handle, housing, screw plug receptacle, and reflector ma be of any suitable construction which wil conveniently serve the purpose of connecting the generating unit to 'a source of electric current and will efliciently reflect the radiant energy emitted thereby. The cartridge or' nerating unit 10 comprises a base made 0 two pieces 11 and 12 of ing material. A threaded brass ferrule or shell 13 is secured over the piece 11 by means of bolts 14 and 15. The nut 14' of bolt 14 is lodged in a suitable recess 16 formed in the piece 11. The head of screw 17 which passes through a central axial bore in piece 11 protrudes slightly from the end of rojection 18 of piece 11, and is threaded into a small conducting bar 19 'which fitsinto registering recesses formed in the contacting faces of pieces 11 and 12. C-shaped resilient supports or cli s 20 and 21 are secured to the outer face 0? piece 12 by screw 22 and bolt 15, res ectively. Screw 22 threads into bar 19, an bolt 15 passes through both pieces 11 and 12 and threads into nut 23, which is held against rotation bythe abutment of one of its faces with the side of the projection 18. Supports or clips 20 and 21 are made of any suitable metal which will retain its resiliency at high'temperatures. Supports 20 and 2 1 have plates-24 of aluminum secured at their outer ends by rivets 25 for a purpose whlch will appear hereinaften A rod or post 26 extends withm a central axial bore in piece 12, its end being threaded in nut 26' which is held against rotation in a recess 27 formed in the rear face of piece 12. .'-The other end of rod 26.is screw threaded to receive heat radiating head 28, which is held in the desired osition by lock nut 29 and washer 31. The sad 28 is preferably made of bronze, brass or other good electncal and heat conductor and has a plurality porcelain or other suitable insulat- I 'of fins, 32, 33 extending radially from its central bod portion. As shown in Figs. 2 and 3 the aflernate fins 33 have enlarge integral bosses 34 extending inwardly to form seats for light generating elements 35, 36, 37 and 38 which in the drawings are shown in rod form. These rods are preferably made of u wdered or granulated caghgiundumand a i I which has been bake .in orms using 1 a a as a binder. The ends of the roos are sintered by an electric arcing process which reduces the resistance of the end portions, so that in operation the ends will not be heated to as high a temperature as the intermediate portions. Small cupshaped discs 39 of aluminumare placed in depressions r sockets in bosses 34 to lie between the ends of the resistor rods andtheir seats in the ends of bosses 34. The purpose of these discs as well as of plates 24 which are riveted to the resilient supports, is to insure good contact between the ends of the resistor rods and their supports, since it has been found that if the rods are in direct contact with the brass, bronze or ferruginous metal, of which the supports 20, 21 and 28 are made, there will be a tendency to are which causes 1pliltting of the sulpport-s and resistor rods and ally reduces t e conductivity of their contacts to such an extent as to make a: further use of the unit ineflicient and sometimes ractically impossible. Since the ends 0 the rods rest in sockets formed in the bosses 34 'and 21, and

and in the lates 24 with their supports 20 cause of the resiliency of these an rts, the rods are firmly held in position.

en in use the radiant energy emitting unit or cartridge is screwed into'thereceptacl'e 8 in the reflector assembly. Upon o eration ofa suitable switch (not shown), t e

. current will flow through the bolt 17,.bar 19, screw 22, support 20, in parallel through resistor rods 35 and 36, head 28, in parallel through rods 37 and 38, support 21, bolt and to the ferrule 13. Since the current passes through the rods 36 and 37- 38. m arallelf respectively,

the rods may be ma e smal er and thus for a given current consumption the total radiatin surface area of the resistor elements is very arg'e.

In ordinary use, the resistor rods are heated to a temperature which will roduce a good red glow. The heat generated in the resistor rods and the heat from the post 26 is conducted to head 28 which, due to its large surface area, is able .to radiate the energy sufliciently fast to prevent a dangerous rise in temperature of the head. The peculiar conformation and disposition of the fins on the headis very desirable since it not only furnishes a large radiating surface, but also offers only a very small obstruction to the radiant ener which is emitted by the rods and which is reflected from reflector 7. The desired result of maintaining the head and post at a relatively low temperature is thus attained without in any we materially decreasing the efliciency of the amp as a whole.

In Figs. 4, 5 and 6, I have shown a. modified construction of a cartridge. For the most part, the construction is similar to that sockets 41 which receive shouldered aluminum plugs 42 havin concave seats for the resistor rods. ,A pair of C-shaped resilient supporting members 43 are secured to the.

base 12 by screw 22 and bolt 15 respectively. A reinforcing C-shaped spring 44 lies within each of the supports 43 and is secured to the base by the same means. The ends of reinforcing springs 44 bear against the riveted heads of shouldered sockets 45. These sockets serve the two-fold purpose of securing radiating and reflecting plates 46 to the ends of supports 43 and also providing seats for the lower ends of the resistor rods. Plates 46 are preferably made of aluminum or a similar material which is a good conductor of heat. As best shown in Fig. 5 these plates are folded back upon themselves so as to form a double thickness where they contact with. the ends of the supports 43. The edges of plates 46'are bent upwardly and downwardly at substantially right angles to the doubled portion. These plates provide a large heat radiating surface and thus maindoes not retain its elasticity at as high a temperature as would be requlred if these plates were not provided. x

The operation of the modified construction shown in Figs. 5 and 6, is, of course, similar to that above described with reference to the construction shown in Figs. 1, 2 and 3. The fluted'head serves to radiate the heat and prevents undue rise in its temperature and the temperature 'of thestem 26, while the plates 46 maintain the supports 43 and reinforcing sgring members 44 at temperatures at which t eir resilienc is'not impaired. The aluminum discs an plates between which the re sistor rods are supported have a relatively low melting fpoint, and therefore without the provision 0 means for radiating the heat from the resistor rod supports the aluminum would be heated to a temperature above its melt ng point, causing the unit to fail and making necessary the replacement of the aluminum discs and plates.

' secure by Letters Patent is:

The invention is capable of variation within equivalent limits and I contemplate such variation as may be desirable in the particular adaptation of the invention shown or in its adaptation to similar devices.

I do not restrict myself in any unessential particulars, but what I claim and desire to 1. In a therapeutic lamp in combination with a reflector having a screw plug receptacle associated therewith, of a radiant energy emitting unit adapted to be screwed into said receptacle to make electrical contact therewith, said unit comprising a plurality of resistor rods forming a path for an electric current, and means for holding said rods in position', including a head having a plurality of heat radiating fins positioned so as to form a minimum obstruction to the emission of radiant energy from said rods and reflector.

2. In a device of the class described, the combination of an insulating base, a plurality of light generating elements, and means for mounting said elements on said base, comprising a post fixed in said base, supports secured to said base and a head secured on the end of said post said head having a plurality of finsextending in planes parallel to said post, the alternate fins having sockets integral therewith forming seats for the ends of said elements.

3. In a device of the class described, the combination of an insulating base, a plurality of resistor rods, and means for mounting said rods on said base, comprising a post fixed in said base, supports secured to said base, and a head secured on the end of said post, said head having a plurality of radially extending heat radiatlng fins formed integral therewith.

4. In a device of the class described, the

combination of an insulatin base, a plurality of resistor rods, and means or mounting said rods on said base, comprising a post fixed in said base, supports secured to said base, and a head secured on the end of said post, said head havin heat radiating fins projecting outwardlyt erefrom.

5. In a therapeutic lamp, in combination with a reflector having a plug receptacle associated therewith, of a radlant energy generating unit adapted to be inserted into said receptacle to make an electrical connection therewith, said unit comprising an insulatin plug, a post mounted thereon, a fluted hea secured at the end of said post, a plurality of resilient supports carried by said plug, resistor rods held between said head and said supports and metallic heat radiating plates secured to said supports adjacent the ends of said rods.

6. In a therapeutic lamp, in combination with a reflector aving an insulating plug receptacle associated therewith, of a radiant energy generating unit adapted to be mounted 1n said receptacle to make an electrical connection therewith, said unit comprising an insulating plug, a post mounted thereon, a

' fluted head secured at the end of said post, a

plurality of resilient supports carried by said plug, resistor rods held between said head and said supports and metallic heat radiating and light reflecting plates secured to said supports.

7. In a thera eutic lamp, in combination with a reflector aving an insulating plug receptacle associated therewith, of a radiant energy generating unit adapted to be mounted in said receptacle to make an electrical connection therewith, said unit comprising an insulating plug, a post mounted thereon, a fluted head secured at-the end of said post, a plurality of resilient supports carried by said plug, resistor rods held between said head and said supports and aluminum plates secured to said supports adjacent the ends of said rods, said plates being bent back upon themselves so as to be of double thickness where juxtaposed to said supports and having their end portions extending outwardly in opposite directions at substantial right angles to the doubled portion.

8. In a therapeutic lamp, in combination with a reflector having an insulating plug receptacle associated therewith, of a radiant energy generating unit adapted to be mounted in said receptacle to make an electrical connection therewith, said unit comprising an insulating plug, a post mounted thereon, a fluted head secured at the end of said post, a. plurality of resilient supports carried by said plug, resistor rods held between said head and said supports and aluminum plates secured to said supports and extending therefrpim in planes substantially parallel to said ro s.

9. In a device of the class described, the combination of an insulating base, a plurality of resistor rods, and means for mounting said rods on said base comprising a post and supports fixed to said base, a head carried by said post, aluminum members interposed between the ends of said rods and said supports and said head, and means for radiating heat conducted from said rods to prevent said aluminum members from melting.

10. In a device of the class described, an insulating base, a resistor rod adapted to be heated by an electric current, means for supporting said rod on said base, and supplying ANDREW A. KULL. 

